jeena/en.javascript.info
1
0
Fork 0
Code Issues Pull requests Projects Packages Wiki Activity Actions

fix

Browse source
This commit is contained in:
Ilya Kantor 2019-09-21 22:12:08 +03:00
parent f80dc03d87
commit 77dc1ba4b3
1 changed files with 5 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

12
1-js/12-generators-iterators/2-async-iterators-generators/article.md
View file

@ -345,20 +345,18 @@ When we expect the data to come asynchronously, with delays, their async counter
Syntax differences between async and regular iterators:
| | Iterators | Async iterators |
| | Iterable | Async Iterable |
|-------|-----------|-----------------|
| Object method to provide iterator | `Symbol.iterator` | `Symbol.asyncIterator` |
| `next()` return value is | any value | `Promise` |
| Method to provide iterator | `Symbol.iterator` | `Symbol.asyncIterator` |
| `next()` return value is | `{value:…, done: true/false}` | `Promise` that resolves to `{value:…, done: true/false}` |
Syntax differences between async and regular generators:
| | Generators | Async generators |
|-------|-----------|-----------------|
| Declaration | `function*` | `async function*` |
| `generator.next()` returns | `{value:…, done: true/false}` | `Promise` that resolves to `{value:…, done: true/false}` |
| `next()` return value is | `{value:…, done: true/false}` | `Promise` that resolves to `{value:…, done: true/false}` |
In web-development we often meet streams of data, when it flows chunk-by-chunk. For instance, downloading or uploading a big file.
We can use async generators to process such data, but it's also worth to mention that there's also another API called Streams, that provides special interfaces to work with such streams, to transform the data and to pass it from one stream to another (e.g. download from one place and immediately send elsewhere).
Streams API is not a part of JavaScript language standard.
We can use async generators to process such data. It's also noteworthy that in some environments, such as browsers, there's also another API called Streams, that provides special interfaces to work with such streams, to transform the data and to pass it from one stream to another (e.g. download from one place and immediately send elsewhere).